Subsystem test framework alters order of child resources prior to transformation in presence of override models

Currently, the JGroups subsystem transformer tests only succeed because the only protocol in the stack with an override model appears first (i.e. add-index=0). If I move this protocol to a different location in the stack, the transformed model comparison fails, because the test framework reorders the children in its Resource model (so that children with override registration come first) before transforming it.